NASA’s Orion spacecraft will take astronauts to destinations at or beyond low Earth orbit. In January 2013, it was announced that ESA would provide the European Service Module (ESM) for Orion’s first uncrewed mission. Derived from ESA’s Automated Transfer Vehicle cargo spacecraft, the ESM will provide life support, propulsion and structural functions for Orion. In February 2017, a contract was signed for a second ESM to be used on Orion’s first crewed flight, which will carry astronauts beyond the Moon and back.

Set to be shipped to the USA around the New Year, ESA’s contribution to NASA’s Orion spacecraft is taking shape at Airbus in Bremen, Germany. This is no test article: the service module pictured here will fly into space by 2020, past the Moon and farther than any other human-rated spacecraft has ever flown before.

The service module will supply electricity, water, oxygen and nitrogen, propulsion and temperature control.

The blue circular frame is the support structure that holds the module as technicians work to get it ready. Yellow ties keep the 11 km of wiring in place as the thousands of components are installed and connected – the ties will be removed before flight. Behind the red support covers are the eight 490 N R-4D-11 thrusters, built by Aerojet.

Technicians are working in three shifts a day to assemble the components that are being shipped from all over Europe to complete this service module in just a few months’ time. In December it will be taken by road to Bremen airport and flown to NASA’s Kennedy Space Center in Florida to meet its crew capsule.

The Propulsion Qualification Module (PQM) is a test module for Orion’s mission critical propulsion system. Currently Airbus, ESA and NASA engineers run a test campaign at the NASA test facility in White Sands (US, New Mexico). Although the PQM and its four propellant tanks will never see space, this is an important step in the development of the Orion programme. Complex systems must first be tested and qualified on Earth before being used as flight hardware in space. The challenge in manufacturing the test tanks was therefore to satisfy the numerous technical specifications, such as cleanliness, fuel compatibility and watertightness, that will also apply to the real propulsion system.

"It is an important milestone, a huge success for the whole team and it perfectly demonstrates our engineering competence. My congratulations to the team but let’s not forget that we still have more tests to come."

Bas Theelen, Orion Programme Manager, Airbus

The flight model will have 33 engines to provide thrust and to manoeuvre the spacecraft on all axes. The test module is equipped with less engines, among them a re-used engine which last flight occurred in 2011 with Space Shuttle Atlantis (OMS–E: Orbital Manoeuvre System Engine). “I am delighted to see these first successful hot firings” says Bas Theelen, Orion Programme Manager at Airbus Space Systems.The test campaign is expected to be terminated at the end of 2017 or the beginning of 2018."

In a series of blog posts based on images taken at the Thales Alenia Space facility in Turin, Italy, we will now have a look at part of Orion’s structure.

This tank bulkhead made of aluminium forms the top platform of the second European Service Module – the one that will fly with astronauts. It is almost 5 metres in diameter.

These pictures show work on the top bulkhead that is located inside the Crew Module Adapter directly under the Crew Module Heat Shield of Orion’s second exploration mission

The bulkhead is a key part of the primary structure providing structural rigidity to the Orion spacecraft much like the chassis of a car. It absorbs the vibrations and energy from launch.

The round holes in the bulkhead allow for tanks to poke through. The four larger holes are for tanks that each hold 2000 l of propellant while the four smaller holes are for three oxygen tanks, and one nitrogen tank.

In the middle of the structure is a square opening for cabling, and helium tanks, more on this part in another blog entry tomorrow…

In a series of blog posts based on images taken at Thales Alenia Space building facility in Turin, Italy, we will have a look at the vertical panels that form part of Orion’s European Service Module primary structure, these images show work on the second service module that will propel astronauts beyond the Moon and provide essentials such as water, air, electricity and power.

The black panels are prepared on a table before being installed into the Service Module vertically. They are made of a lightweight composite material known as carbon-fibre reinforced-plastic. The honeycomb structure provides rigidity while keeping weight down.

The large holes when installed keep the weight down even more but also allow the technicians and engineers access to the mass of meticulously laid cables to be installed – over 11 km in total! The silver circles are mounting points for equipment and cables. Most of these will be installed in Bremen, Germany, at the Airbus integration hall where the complete service module is assembled.

Inside the four panels two helium tanks will be installed that will be used to push propellant to Orion’s engines during its mission.

Brackets for holding the tank bulkheads (discussed in this blog post) are already attached to the bottom bulkhead and ready for installing the top bulkhead. In the photo below the engineers are standing in the hole that allows room for the propellant tanks.

These images show the beginnings of the spacecraft structure that will send human beings further from Earth than ever before – we will keep you updated in more blog posts.

Wrapping up our blog entries on the frame of the second European Service module for Orion, these pictures show the completed internal structure for Flight Model-2. It will support up to four astronauts and send them further than any human being has ever been from Earth in a few years.

The pictures show the two circular tank bulkheads in place, bolted to the vertical panels. The top ring will attach to the Crew Module Adapter that connects the Orion capsule to the service module.

The pictures were taken at the Thales Alenia Space facility in Turin, Italy, in November 2017.

This structure can be seen as the chassis of the Orion spacecraft, providing structural rigidity while absorbing vibrations and energy from launch.

The holes are to save weight and accommodate future payloads. It will also hold all the other elements together such as the spacecraft’s thrusters, water tanks, fuel tanks, gas tanks, electronics and wires.The top bulkhead is thicker as it handles more loads. Orion’s storage tanks are supported from the top bulkhead which distributes the forces from 9 tonnes of propellant between the European Service Module structure and NASA structures such as the Crew Module Adapter and the launcher fairing, while the lower platform “only” provides support to prevent the tanks from swinging.

Shipment of ESM-1 to the US is scheduled not earlier than March 2018 with a risk of further delays mainly because of delayed supplier deliveries. There are no margins in the ESM schedule so any problems in manufacturing, integration and test activities on the critical path may result in further delay. The critical path is driven by the high-pressure gas valves delivery from a US supplier but several other pieces of equipment are just behind them. The functional test model was delivered and accepted in May by NASA/Lockheed Martin.

The procurement and manufacturing of ESM-2 hardware was authorised to maintain the schedule, while the qualification of the design is not complete and waivers are not all processed. This risk is controlled by the project through risk assessment at each of the equipment Manufacturing Readiness Reviews. For ESM-3, studies are ongoing to assess the design upgrades requested by NASA.

Shipment of ESM-1 to the US is scheduled not earlier than March 2018 with a risk of further delays mainly because of delayed supplier deliveries. There are no margins in the ESM schedule so any problems in manufacturing, integration and test activities on the critical path may result in further delay. The critical path is driven by the high-pressure gas valves delivery from a US supplier but several other pieces of equipment are just behind them. The functional test model was delivered and accepted in May by NASA/Lockheed Martin.

The procurement and manufacturing of ESM-2 hardware was authorised to maintain the schedule, while the qualification of the design is not complete and waivers are not all processed. This risk is controlled by the project through risk assessment at each of the equipment Manufacturing Readiness Reviews. For ESM-3, studies are ongoing to assess the design upgrades requested by NASA.

Yessir. Classic recipe for a scheduling disaster notwithstanding the statement about risk control. The latter is really management-talk for "we can't control it but we are trying".

Also interesting to read that the critical path is driven by a US supplier whereas earlier reports had indicated it was European suppliers causing the delays.